U.S. Vice President Dick Cheney was deeply involved in the leak of a former CIA agent's identity in the summer of 2003, Special Prosecutor Patrick Fitzgerald said Tuesday.

In his opening statement in the CIA leak trial, Fitzgerald said Cheney told his chief of staff I. Lewis "Scooter" Libby in 2003 that Wilson's wife, Valerie Plame Wilson, worked for the CIA and Libby spread that information to reporters.

Fitzgerald said Libby "he made up a story" when the FBI and grand jury asked about what he had done in the leak case.

Libby, who was charged with perjury and obstruction and resigned in October 2005, told investigators probing who had leaked Wilson's identity that he learned her identity from NBC News reporter Tim Russert, not from the vice president. But Fitzgerald told jurors on Tuesday that was a lie because Libby had already been discussing the matter inside and outside of the White House.

"You can't learn something on Thursday that you're giving out on Monday," he said.

The disclosure of Wilson's identity in July 2003 set off a chain of events, which included the appointment of Fitzgerald as the special prosecutor to investigate the leak case and a grand jury's indictment of Libby for lying to investigators about his own conversations with reporters regarding Wilson.

Wilson's identity was made public in a newspaper column, days after her husband, Joseph Wilson, a former diplomat, criticized the Bush administration for "twisting" intelligence to justify the Iraq war.